Electrostatic Origins of CO2-Increased Hydrophilicity in Carbonate Reservoirs

Injecting CO2 into oil reservoirs appears to be cost-effective and environmentally friendly due to decreasing the use of chemicals and cutting back on the greenhouse gas emission released. However, there is a pressing need for new algorithms to characterize oil/brine/rock system wettability, thus better predict and manage CO2 geological storage and enhanced oil recovery in oil reservoirs. We coupled surface complexation/CO2 and calcite dissolution model, and accurately predicted measured oil-on-calcite contact angles in NaCl and CaCl2 solutions with and without CO2. Contact angles decreased in carbonated water indicating increased hydrophilicity under carbonation. Lowered salinity increased hydrophilicity as did Ca2+. Hydrophilicity correlates with independently calculated oil-calcite electrostatic bridging. The link between the two may be used to better implement CO2 EOR in fields

Seroepidemiology Of Human Cytomegalovirus In Pregnant Women and their Neonates In Kerman City During 2005

Abstract: Introduction: Human Cytomegalovirus (HCMV) or Human Herpes Virus Type-5(HHV-5) is a member of herpesviridae placed in subtype beta herpesvirinae. CMV is a ubiquitous pathogenic virus and can infect humans all through their life. Prevalence of CMV infection in developed countries is about 45% and in developing countries it varies up to 100%. CMV infection during pregnancy is very important, because it can threat life of both mother and her fetus, and it can cause congenital defects. Maternal infection is a determining factor in neonatal infection. The present study was conducted to determine the prevalence rate of CMV infection as well as the relationship between underlying factors of this infection in women and their neonates in Kerman. Methods: ELISA technique and Diagnostic Kits (EIA WELL, Rome, Italy) were used to determine the seroprevalence of 794 samples (397 maternal, 397 neonatal) collected from 5 delivery centers in Kerman. Results: The frequency distributions of maternal primary infection, secondary infection, immune mothers and seronegative cases were respectively 0.76% (3 cases), 32.24% (128 cases), 59.7% (237 cases) and 7.3% (29 cases). Seroprevalence rate for CMV-IgG and CMV-IgM of mothers were respectively, 33.8% (134 cases) and 91.94% (365 cases). No significant relationship was found between CMV infection and factors of mother’s age and occupation, husband’s occupation, number of children, parity, family income, previous history of abortion, pervious history of blood transfusion and organ transplant, febrile disease during pregnancy and place of residency; however, mother’s educational level showed a significant relation (P=0.38). Conclusion: Due to high prevalence rate of CMV found in this study, further studies about the diagnosis, epidemiology and detection of CMV primary infections in mothers and their neonates, are highly recommended. . Keywords: HCMV, Seroepidemiology, Maternal Infection, Primary Infection, Secondary Infection, ELIS

Identification of chemical components in Zataria multiflora callus by GC-Mass analysis

Background and objectives: A modern biotechnological technique to obtain useful natural products from plants is to isolate them from their callus. Zataria multiflora is a bushy herb of the Lamiaceae family known for its stimulant, antibacterial, antioxidant and expectorant effects in Iranian folk medicine.  The present study has investigated the induction of callus tissue and identification of its chemical compounds by GC-Mass analysis. Methods: The plant seeds of were sterilized and cultured in petri dishes lined with MS medium. After the emergence of seedlings, leaf segments were transferred to another MS medium supplemented with 2 mg/L 2,4- Dichlorophenoxyacetic acid + 1 mg/L  Kinetin. The petri dishes were incubated in a growth chamber at 24 °C with photoperiod of 16/8 (light/dark). The methanol extract of the calli were extracted after 2 month of callus induction and the chemicals were analyzed by gas chromatography-mass spectrometry (GC-MS). Reults: GC-MS analysis showed 20 different compound including different fatty acids, phytosterolls and phenolic compounds. Linolenic acid methyl ester (13.38%), thymol (10.34%), cyclohexasiloxane dodecamethyl (7.50%) and р-cymen (7.30%) were the dominant compounds, respectively. Conclusion: This novel   finding showed that in vitro production of thymol and other terpenoids by callus culture could be optimized for wide industrial and pharmaceutical applications via bioreactor systems employment

Optimization of callus induction of Zataria multiflora under the effect of different plant growth regulators and explant source

Background and objectives: The Lamiaceae family is rich in favorable secondary metabolites which have different medicinal properties and also use in food, cosmetic and sanitary industry. Zataria multiflora Boiss. is an aromatic and bushy plant containing specific pharmaceutical components which is only distributed in certain regions of Iran. Tissue culture technologies could be suitable for in vitro production of Zataria. Methods: In this study, callus production and callus related traits of Zataria was evaluated at in vitro condition. Callus induction was performed on Murashige and Skoog (MS) medium containing different levels of plant growth regulators including different cytokinins (Kinetin, benzyl amino purine) and auxins (2,4 dichlorophenoxyacetic acid and naphtalen acetic acid) and two different explant (hypocotyl and leaf). Results: The friable calli with yellow-green color only appeared from leaf explants on three different treatments including: 1: 2.5 (mg/L 2,4-D); 2: 2 (mg/L  2,4-D); 3: [2 (mg/L) 2,4-D+ 1 (mg/L Kin].  The best callus induction (75%) was obtained at 2,4-D (2 mg/L ) + Kin (1 mg/L) after 2 month of incubation under the photoperiod of 16/8 (light/dark). The highest callus growth rate (CGR) (0.072 mm/day) and callus fresh weight (0.135 g) were denoted to the treatment of 2 mg/L (2,4-D).  Conclusion: The benefits of the protocol described here include the possibility of its use throughout the callus culture for commercial production of suitable secondary metabolites of Zataria in rapid time and huge scale

A study of the performance of the LSWA CO2 EOR technique on improvement of oil recovery in sandstones

Low salinity water is an emerging enhanced oil recovery (EOR) method that causes wettability alteration towards a favorable state to reduce residual oil saturation, while water alternating gas (WAG) is a proven EOR process that enhances oil recovery by controlling mobility of both water and gas. Therefore, combining the two EOR processes as low salinity water-alternating CO2 EOR injection (LSWA CO2) can further improve oil recovery by promoting the synergy of the mechanisms underlying these two methods.Core flooding experiments, contact angle, interfacial tension (IFT), and CO2 solubility measurement in oil and brine were conducted to investigate the viability and performance of LSWA CO2 in sandstone reservoirs. A favorable wettability alteration, along with IFT reduction and mobility control, are the mechanisms that contribute to residual oil mobilization efficiencies during the LSWA CO2 EOR process. In addition, LSWA CO2 core flooding experiments result in a significant incremental oil recovery.Three smart waters were tested in our research, to examine the impact of changing cationic composition on oil recovery. The solutions are designed brines as NaCl (SW1), MgCl2 (SW2), and KCl (SW3). Of the three solutions, SW1 yields the highest incremental oil recovery and highest IFT reduction. In addition, it results in a favorable wettability alteration towards a more water-wet state.In all cases, introducing CO2 to the brine/oil system shows a great advantage in terms of enhancing wettability modification, promoting IFT reduction, and controlling the displacement front of the injected fluid through mobility control

Coal-on-a-Chip: Visualizing Flow in Coal Fractures

© 2017 American Chemical Society. Geomaterial microfluidics are the next generation of tools necessary for studying fluid flows related to subsurface engineering technologies. Traditional microfluidic devices do not capture surface wettability and roughness parameters that can have a significant influence on porous media flows. This is particularly important for coal seam gas reservoirs in which methane gas is transported through a well-developed system of natural fractures that display unique wettability and roughness characteristics. A coal geomaterial microfluidic device can be generated by etching a fracture pattern on a coal surface by using three-dimensional laser micromachining; however, it is unclear if the resulting surface properties are representative of real coal. In an effort to generate a realistic coal microfluidic device, we characterize coal surface roughness properties from real coal cleats. We then compare these results to the roughness of the patterns, generated from laser etching. Roughness measurements in real coal fractures show that cleats and microfractures are mostly oriented parallel to the coal beddings rather than perpendicular to the bedding, which is important when selecting coal for fabrication of a microfluidic device since we find that the natural microfractures influence the resulting roughness of etched fractures. We also compare resulting coal/brine/gas contact angles under static and dynamics conditions. The contact angle for coal is highly heterogeneous. Surface roughness and pore pressure may influence the contact angle. With the aid of the coal geomaterial device, the effect of these parameters on coal wettability can be explored and a range of possible coal contact angles can be visualized and represented. The geomaterial fabrication, as outlined herein, provides a tool to capture more realistic coal surface properties in microfluidics experiments

Microfluidics for Porous Systems: Fabrication, Microscopy and Applications

© 2018, Springer Nature B.V. No matter how sophisticated the structures are and on what length scale the pore sizes are, fluid displacement in porous media can be visualized, captured, mimicked and optimized using microfluidics. Visualizing transport processes is fundamental to our understanding of complex hydrogeological systems, petroleum production, medical science applications and other engineering applications. Microfluidics is an ideal tool for visual observation of flow at high temporal and spatial resolution. Experiments are typically fast, as sample volume is substantially low with the use of miniaturized devices. This review first discusses the fabrication techniques for generating microfluidics devices, experimental setups and new advances in microfluidic fabrication using three-dimensional printing, geomaterials and biomaterials. We then address multiphase transport in subsurface porous media, with an emphasis on hydrology and petroleum engineering applications in the past few decades. We also cover the application of microfluidics to study membrane systems in biomedical science and particle sorting. Lastly, we explore how synergies across different disciplines can lead to innovations in this field. A number of problems that have been resolved, topics that are under investigation and cutting-edge applications that are emerging are highlighted